#include <algorithm>
#include <iostream>
using namespace std;

const int kMaxN = 2012;
const int kInf = 1e9;

int pos[kMaxN], dp[kMaxN];

int main() {
  freopen("wifi.in", "r", stdin);
  freopen("wifi.out", "w", stdout);
  ios::sync_with_stdio(0), cin.tie(0), cout.tie(0);

  int n, A, B;

  cin >> n >> A >> B;
  for (int i = 1; i <= n; i++) {
    cin >> pos[i];
  }
  sort(pos + 1, pos + 1 + n);

  fill(dp, dp + n + 1, kInf);
  dp[0] = 0;
  A *= 2;
  for (int i = 1; i <= n; i++) {
    for (int j = 0; j < i; j++) {
      dp[i] = min(dp[i], dp[j] + A + (pos[i] - pos[j + 1]) * B);
    }
  }
  cout << dp[n] / 2 << (dp[n] % 2 ? ".5\n" : "\n");
  return 0;
}